1. Field of the Invention
The present invention relates to a process to produce an electrically conductive polymer comprising poly(dithiophene) (PDTP), electropolymerizing .alpha.,.alpha.-thiophene dimer, in the presence of an organometallic compound, such as a metal phthalocyanine, as a dopant.
2. Description of the Art
A number of references disclose some heteroatom polymers which have electrochemical properties both in the presence and absence of charged dopants. These include for example the following:
A. Ootani et al., in Japanese Patent No. S60-188931, disclose an electrochromic display element synthesized by an electrochemical polymerization of a solution of pyrrole or thiophene and sodium bathophenoanthroline - sulfonate-iron complex or phthalocyanine.
K Kaneto et al., in the Japanese Journal of Applied Physics, Vol. 22, No. 7, pp. L412-L414 (1983) disclose some characteristics of electro-optic devices using conducting polymers polythiophene and polypyrrole films.
K Kaneto et al., in the Japanese Journal of Applied Physics, Vol. 25, No. 7, July 1985, pp. L553-L555 disclose a heterojunction consisting of conducting polymers of polythiophene.
J. Castonguay et al., in Thin Solid Films, Vol. 69, pp. 85-97 (1980) disclose the deposition of thin polymeric films using monomer molecules which have semiconductor properties. Those monomers selected were phthalocyanine, copper phthalocyanine, tetracyanodimethane (TCNQ) and its triethylamine salt and the perylene-iodine complex. The monomer having a minimal residence time of about 10 sec. in a glow discharge were minimally fragmented.
T. Osaka et al., in the Bulletin of the Chemical Society of Japan, Vol 59, pp. 2717-2722 (1986) disclose electrode of glassy carbon/polypyrrole/(tetrasulfonatophthalocyaninato) cobalt.
T. Inabe, et al., in Polymer Materials Science Engineering, Vol. 49, pp. 89-93 (1983) disclose electroconducting polymers of polyamides (aramides) and metal phthalocyanines.
T. Skotheim et al., in the Journal of the Chemical Society, Chemical Communications, pp. 612-613 (1985) disclose the formation of conductive polymers of polypyrrolesulfonated cobalt phthalocyanine. These electrodes are stable on repeated recycling between -1.0 and 1.2 V in acetonitrile/tetraethylammonium tetrafluoroborate, and lose only 35% of the cobaltphthalocyanine in aqueous electrolytes. The conductivity of the films increases on storing in air, in contrast to normal films containing BF.sub.4 -+counterions which show a decrease in conductivity.
T. Inabe et al., in Synthetic Metals, Vol. 9 pp. 303-316 91984 (1984) disclose the preparation of environmentally stable, flexible, oriented electrically conductive fibers. Solutions of phthalocyanine containing macromolecular, [Si(Pc)O].sub.n, or molecular, NiPc, a metal precursor and a host polymer, "KEVLAR.RTM.", a trademark of the DuPont Company of Wilmington, Delaware for an aromatic polyamide fiber of extremely high tensile strength are wet spun to yield, after halogen or electrochemical doping, strong, air-stable fibers with thermally activated electronic conductivities as high as 51/4.sup.-1 cm.sup.-1.
None of the above references individually or collectively disclose or suggest the present invention of simultaneously producing a metal phthalocyanine doped conducting polymer of poly(dithiophene). The present invention is very useful to provide an electrically conductive polymer based on dithiophene having a metal phthalocyanine as a dopant.